--- title: "Percentage and decimal equivalents" description: "Solve problems requiring knowledge of percentage and decimal equivalents of 1/2, 1/4, 1/5, 2/5, 4/5 and fractions with denominators that are multiples of 10 or 25" canonical: https://lightmysky.com/learn/mathematics/percentage-and-decimal-equivalents-mt_4ubP_RMg9o source: https://lightmysky.com/learn/mathematics/percentage-and-decimal-equivalents-mt_4ubP_RMg9o.md retrieved: 2026-10-19 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Percentage and decimal equivalents Solve problems requiring knowledge of percentage and decimal equivalents of 1/2, 1/4, 1/5, 2/5, 4/5 and fractions with denominators that are multiples of 10 or 25 Subject: Mathematics · Area: Fractions · Ages 9 to 10 Page: https://lightmysky.com/learn/mathematics/percentage-and-decimal-equivalents-mt_4ubP_RMg9o ## Ready when they can - State that 1/5 = 20% = 0.2 and use this to find 20% of 60 - Convert 3/4 to 75% and to 0.75 - A shop offers 25% off a £40 item — what is the sale price? ## Lesson: Fractions, decimals, and percents together You already know that fractions and decimals can show the same amount. Percent is a third way to write it. Percent just means 'out of 100'. A few fractions have percent and decimal partners worth remembering: 1/2 = 50% = 0.5, 1/4 = 25% = 0.25, 1/5 = 20% = 0.2, 2/5 = 40% = 0.4, and 4/5 = 80% = 0.8. *(drawing: One quarter of the circle is shaded. That's 25%, or 0.25 as a decimal.)* **Example.** To find 20% of 60, remember 20% is the same as 1/5. So 20% of 60 is 1/5 of 60, which is 60 ÷ 5 = 12. **Example.** A shop takes 25% off a £40 jacket. Since 25% = 1/4, the discount is £40 ÷ 4 = £10. The sale price is £40 minus £10, which is £30. **Tip.** Fractions with a denominator of 10, 20, 25, or 50 turn into percents fast. Scale the fraction so the denominator becomes 100. For 7/20, multiply top and bottom by 5 to get 35/100, which is 35%. **Recap.** Once you know 1/2, 1/4, 1/5, 2/5, and 4/5 as percents and decimals, you can solve money and amount problems without long division. ## Practice 15 questions on this page, each with its working shown. ## Needs first - [Fraction-Decimal Equivalents](https://lightmysky.com/learn/mathematics/fraction-decimal-equivalents-mt_DRlbMok2lT) - [Understanding Percentages](https://lightmysky.com/learn/mathematics/understanding-percentages-mt_ZM9mhHsyYZ) ## Opens up - [Decimals and fractions (age 10+)](https://lightmysky.com/learn/mathematics/decimals-and-fractions-age-10-mt_4K1dr204Hi) - [Complex Multi-Step Problems](https://lightmysky.com/learn/mathematics/complex-multi-step-problems-mt_GpltXPoaoc)